I started that thread over 5 years ago thinking there would be general interest in getting rid of duallies, but instead found most RV owners feel safer with duallies. I personally don’t care for duallies at all, and prefer singles.
Converting from duallies to singles will have limited market appeal, so I now expect transition to singles will come slowly from chassis that are designed that way from very beginning. Even better is when new chassis have four equal-size wheels and tires so carrying a spare is more effective. It also allows tire rotation.
Some military trucks have 4 large equal-size wheels and tires, and recently I’ve noticed some/many commercial electric vehicles are being designed from onset with 4 equal wheel/tires. Additionally, 4WD motorhomes designed for serious off-road use tend to avoid dual wheels. I hope 4 equal tires is the long-term solution for motorhomes other than maybe diesel pushers (because of their extreme rear weight bias).
Here are some “factory” vehicles with single-rear-wheels. I know you asked about individuals doing a conversion, but these have higher level of engineering, so shows it can be done successfully. Note the large electric bus seems to have larger tires on rear axle versus front.
Not what you asked for, but at least these show your interest is not crazy. Also shows some progress over previous 5 years.
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